NATIONAL HARBOR, Md. — Lockheed Martin has eight completed F-35 fighters it is waiting to ship to the U.S. military after the discovery of a Chinese alloy in the aircraft prompted the Defense Department to halt further deliveries.

In an interview with Defense News on Tuesday, Greg Ulmer, Lockheed Martin’s executive vice president for aeronautics, said the company has continued to build F-35s while it awaits a waiver from the department allowing deliveries to resume.

Ulmer said it would take about a month or two of building undelivered F-35s before the company would run out of space to store the finished fighters. But he added that Lockheed does not think it will reach that point and expects the department to issue the waiver “sooner rather than later.”

“There’s quite a bit of room locally, so I don’t necessarily see that as an issue,” Ulmer said at the Air Force Association’s Air, Space and Cyber Conference in National Harbor, Maryland. “My belief is we would get through the waiver before that.”

The Pentagon on Sept. 7 announced it had temporarily halted F-35 deliveries after it was discovered a magnet — one part of a key Honeywell-made component in the aircraft’s engine — was made with a cobalt and samarium alloy that came from China. This raised concerns that the magnet may violate the Defense Federal Acquisition Regulation, and the F-35 Joint Program Office ordered the Defense Contract Management Agency to stop accepting F-35s for the time being.

The JPO said earlier this month the part does not transmit information, nor jeopardize the security or flight safety of the aircraft.

Ulmer said Lockheed Martin is working with its network of subcontractors to find out how the Chinese alloy entered its supply chain for years.

Lockheed has long had a process under which subcontractors — and even their subcontractors — deliver certificates of conformance verifying the origins of the parts and materials they deliver, Ulmer said. But at some point it failed, he added.

“We’re doing our homework and diagnostics to go [review the process] all the way down the chain, to figure out where in the chain it broke,” Ulmer said. “That’ll help inform us what we need to do to change the approach, not just from an F-35 perspective but, more broadly, relative to our supply chain.”

Ulmer said he has no reason to believe someone in the process deliberately obfuscated the origin of the material, but that the investigation will continue.

In a roundtable with reporters at the conference later on Tuesday, Andrew Hunter, the Air Force’s assistant secretary for acquisition, technology and logistics, said issues like this and the COVID-19 pandemic have highlighted the complexity of the supply chain networks on which the Defense Department relies.

“That alloy was something that should never have been in our supply chain, and it should have been detected much earlier,” Hunter said. “These supply chains are not static. So it does require constant vigilance to make sure that our supply chains are resilient, they are secure, and that we know where stuff is coming from and whether they’re compliant.”

Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at He has traveled to the Middle East to cover U.S. Air Force operations.

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